The present invention relates to an electromagnetic valve where configuration and assembling of a current conduction system is simplified.
In an electromagnetic valve provided with a valve portion having a valve body switching flow paths according to approaching to/separating from a valve seat in a valve main body and a solenoid portion which drives the valve body in directions of approaching to/separating from the valve seat, a current conduction terminal conducting current to the solenoid portion is normally derived to the outside from between a yoke provided outside a coil in the solenoid portion and the coil.
For this reason, it becomes necessary to provide means for electrically insulating a current conduction terminal in the solenoid portion to derive it to the outside, which results in requirement for much labor and time in assembling the means. Also, in particular, in a case that the electromagnetic valve is formed in a water-proof/drip-proof type, it is necessary to consider special means for liquid-tight treatment of the deriving portion of the current conduction terminal in the solenoid portion. Therefore, such a problem occurs that the structure required therefor is complicated and much time and labor are required for assembling work.
A technical problem of the present invention is to provide an electromagnetic valve where a configuration and an assembling of a current conduction system to a solenoid portion are simplified and an assembling easiness has been improved eventually.
A further specific technical problem of the present invention is to provide an electromagnetic valve where insulating properties of a solenoid portion and its current conduction system can easily be secured.
Another technical problem of the present invention is to provide an electromagnetic valve where an insulating structure of a current conduction system to a solenoid portion is simplified by utilizing an electrical insulation performance of a valve main body made from synthetic resin effectively.
Another technical problem of the present invention is to provide an electromagnetic valve where a water-proof/drip-proof property of a solenoid portion and its current conduction system can easily be secured.
An electromagnetic valve of the present invention for solving the above problem is an electromagnetic valve comprising a valve portion having a valve body for switching flow paths according to approach to/separation from a valve seat within a valve main body and a solenoid portion which drives the valve body so as to approach to/separate from the valve seat, wherein the valve main body is formed from an electric insulating synthetic resin; in a state where a current conduction terminal constituting a current conduction system of the solenoid portion has been inserted into a terminal insertion hole opened in a contact face with a solenoid in the valve main body, the solenoid portion and the valve portion are fixed to each other; and an opening for inserting a contact terminal which extends from the outside to the current conduction terminal in the terminal insertion hole to be electrically connected thereto is provided in the valve main body.
In a preferable embodiment of the electromagnetic valve of the present invention, the contact terminal is provided to a terminal box mounted to the valve portion and/or the solenoid portion; a terminal block constituting a base portion of the terminal box is fixed to the solenoid portion, and a connector for connecting the contact terminal connected to the current conduction terminal to an electronic part for a current conduction circuit and an external power source is provided in a board assembly mounted on the terminal block; and a contact terminal for connecting to a current conduction terminal provided in the board assembly is formed by a pair of resilient contact pieces which are elastically inserted through an opening communicating with the terminal insertion hole of the solenoid in the valve main body from the outside of the valve main body to hold the current conduction terminal in the terminal insertion hole.
In the electromagnetic valve having the above configuration, the valve main body is formed from the electrically insulating synthetic resin, the solenoid portion and the valve portion are fixed to each other in the state where the current conduction terminal to the solenoid portion has been inserted into the terminal insertion hole in the valve main body, a contact terminal provided in an external terminal box or the like is brought into contact with the current conduction terminal in the terminal insertion hole, further preferably, the contact terminal is formed by a pair of resilient contact pieces such that the contact pieces are inserted through an opening communicating with the terminal insertion hole of the valve main body to hold the current conduction terminal in the terminal insertion hole, so that the configuration and the assembling of the current conduction system to the solenoid portion can be simplified. In addition, by utilizing the valve main body comprising the electrically insulating synthetic resin effectively, a function serving as a housing of the connection portion of the current conduction terminal and the contact terminal is imparted to a portion of the valve main body, so that the insulating structure of the current conduction system of the valve main body is remarkably simplified and the insulation performance can easily be secured.
Furthermore, in the electromagnetic valve of the present invention, the magnetic cover provided outside the coil in the solenoid portion is formed in such a shape as to constitute an outer shell of the solenoid portion to cover it in a liquid-tight manner, the valve main body is fixed to the opening end side of the magnetic cover in a liquid-tight manner, and the contact terminal connected to the current conduction terminal can be inserted into the opening of the valve main body in a liquid-tight manner, so that a water-proof/drip-proof properties of the solenoid portion and its current conduction system in the electromagnetic valve can easily be secured.